6.4 Hemi longevity

[DonFitzwater]

Any of you boys and girls have much experience with the 6.4 Hemi? I've got one in my work truck and it's sitting at 3000 hours and 57,000 miles. No running problems whatsoever but it will very randomly blow smoke on startup. This is never consistent and I'd say it happens maybe once or twice a month. Truck has no other problems engine wise. Anybody have anything to report on the big Hemi at higher mileages? Also, what temp are you guys seeing during normal operation? My truck runs 212-225 f

 

[TFucili]

I only had about 43K when I sold mine. It did the blue puff a fair bit when new, but after hooking onto a trailer and really working it that settled down. It would still do it occasionally, but very intermittent. The PCV setup is totally different on the 6.4 versus the 5.7, and I just assumed it was due to that design. I have read that the a PCV change requires a complete intake manifold???

Your temps seem pretty much in line. The oil temps would really climb when pulling heavy, like 240+ IIRC.

Other than early 6.4s that had wrist pin issues, the only failures I have seen/read are cam and lifter failures, same as the 5.7.

 

[Wayne M.]

Don, is this truck parked on a hill, nose up when this happens?
The smoke thing is a rampant issue. Look over on durangoforum and you’ll see. My ‘14 has done it randomly and for sure if parked on a steep nose up hill since new. I know of a couple of other 5.7’s locally and they do it.
Dealer denies a problem vehemently
I don’t think it matters weather it’s a 5.7 or 6.4. They do it.

 

[jgillott]

My friend in GA recently traded in he 2015 6.4 for a 2019 6.4. The 2015 had something like 140K on it when he sold it and had no complaints from what I understand.

 

[DonFitzwater]

Don, is this truck parked on a hill, nose up when this happens?
The smoke thing is a rampant issue. Look over on durangoforum and you’ll see. My ‘14 has done it randomly and for sure if parked on a steep nose up hill since new. I know of a couple of other 5.7’s locally and they do it.
Dealer denies a problem vehemently
I don’t think it matters weather it’s a 5.7 or 6.4. They do it.

Flat ground is when I usually see it. I’ve never had a 5.7 smoke......lots of ticky ticky from what I’ve heard but no smoking.

 

[DonFitzwater]

I only had about 43K when I sold mine. It did the blue puff a fair bit when new, but after hooking onto a trailer and really working it that settled down. It would still do it occasionally, but very intermittent. The PCV setup is totally different on the 6.4 versus the 5.7, and I just assumed it was due to that design. I have read that the a PCV change requires a complete intake manifold???

Your temps seem pretty much in line. The oil temps would really climb when pulling heavy, like 240+ IIRC.

Other than early 6.4s that had wrist pin issues, the only failures I have seen/read are cam and lifter failures, same as the 5.7.

I had a 2015 chassis cab with a 6.4 and it was a beast. It did really well until I tried “Cummins hill”, a 13% grade north of Fairbanks. I had a 500 gallon water tank full in the back and a big bobcat on a 2500 pound trailer........it climbed it but that’s when I realized there is no replacement for a Cummins.

 

[Wayne M.]

I see Verizon has 6.4 powered Ram bucket trucks now, and I saw one scooting out from a stop light. It had some giddyap, but for sure no replacement for the 5” stroke Cummins!

 

[Timd32]

I see a lot of posts about the PCV system pushing oil into the intake, it's like a constant back and forth to add a catch can to prevent this from happening, friend added one to their 6.4 and it does fill up that can maybe half way inbetween oil changes, it might be 6oz? Of oil, I will ask them.

My 6.2 chevy same thing folks on that forum say the same thing add a catch can.

Could it be the intake has some oil collected in it?

I have not added one to mine, but I am doing OA and pushing the longer end of oil changes, because I read posts like this anyway and they eventually have some sort of issue. I'm pretty close to only my second oil change so will see where the TBN and metal counts are. It too is a work truck so figure it a good test vehicle.

Maybe I will add a catch can to see what's up.

 

[dieselshadow]

From what I understood the 6.4 car Hemi and the 6.4 truck Hemi are completely different. I tried to buy a catch can but the intake manifold was different and nobody had it available as a kit. I read somewhere (but never verified) that the PCV was all built into the intake manifold on the truck engines unlike the cars. So I left it be and didn’t lose any sleep over it.

 

[Timd32]

10-4, yeah I just stopped for fuel, I have may e 8k on my oil right now still just barely off the full mark, so I have been just trying to keep track that way, if I see a tick in consumption will pull a line and check.

 

[campertruck]

I have a 2016 6.4 in a 3500 Chassis Cab with the Aisin. It has 30,000 miles and has performed flawlessly. I have 4:44 gears and it loves carrying my camper on the back. My brother has a 2017 2500 pickup and he has 3:73 gears and that feels like a highway cruiser. It will run 75mph with the MDS on getting somewhere from 16-18 mpg all day. Around town we both get 11-13 mpg. They are good engines and if you just change your oil, you should do well with them.

 

[campertruck]

I have a 2016 3500 Chassis Cab with the Aisin transmission running 4:44 gears. Truck carries an 11 foot camper on the back and has performed flawlessly. I am at 30,000 miles and the truck feels like new. My brother has a 2017 2500 with the 6.4 and 3:73 gears. His loves 80 mph and at 75 mph the MDS is on and he gets 16-18 mpg regularly on trips with it, while mine carrying the camper gets 9-11 mpg depending on speed. Around town both of us are schlepping with 11-13 mpg. Neither one has given any issues, his has almost 90,000 miles and sounds the same as mine does. Good trucks and good engines, I would recommend them . Get 4:10 gears if you plan on towing with the pickups, it's a big difference. The new 8 speed transmission should really let that engine shine.